In India, Big Brother just wants to help. The country's 1.2 billion citizens are to be issued with a biometric identity card in an attempt to improve the delivery of India's inefficient public services – a move civil liberties' activists are condemning as the act of a "surveillance society".

This month, the country began the ambitious scheme of issuing everyone with a unique identity number. Within the first five years of the scheme, giant computer servers will hold the personal details of at least 600 million people. The introduction of what will be one of the world's most ambitious IT projects will cost an estimated £1.5bn.

The scheme is the brainchild of Nandan Nilekani, one of India's best-known software tycoons and now head of the government's Unique Identification Authority. "We are going to have to build something on the scale of Google but it will change the country … every person for first time [will] be able to prove who he or she was."

The country's red tape is legendary: Indians have dozens of types of identity verification, ranging from electoral rolls to ration cards, yet almost none can be used universally. The new system will be a national proof of identity, effective for everything, from welfare benefits to updating land records.

Nilekani said the scheme would help the poor especially. Moving from one state to another – a regular occurrence for poor villagers in search of work – often meant benefits were withdrawn because proof of residence was lacking. "This will mean maids and labourers … a hundred or two hundred million people – will be able to access welfare benefits for the first time without any questioning who they are."

Eventually, cards will hold the person's name, age, and birth date, as well as fingerprint or iris scans, though no caste or religious identification. "We are not profiling a billion people. This will provide an ID database which government can access online. There will be checks and balances to protect identities," said Nilekani, who has also been in talks to create a personalised carbon account so that all Indians might buy "green technologies" using a government subsidy.

Doubts have been raised over privacy and the complex security needed to police such the system, as well as concerns that the project is just too ambitious. "We could have a hacking Olympics," said Guru Malladi, a partner at Ernst & Young.

Civil liberty campaigners fear the card could be a tool of repression.

Nandita Haskar, a human rights lawyer, said: "There's already no accountability in regard to violations of human and civil rights. In this atmosphere what are the oversight mechanisms for this kind of surveillance?"